The email service features end-to-end encryption; emails stored on ProtonMail's servers also are encrypted and thus can't be accessed.

"Not even ProtonMail has the ability to read the emails of our users, and thus it's technically impossible for us to hand over user messages to third parties," Yen told TechNewsWorld.

Based in Switzerland, its servers are out of reach of United States authorities.

All ProtonMail client-side code is open source and is reviewed by the ProtonMail community.

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The basic service is free, offering users 1 GB of storage.

ProtonMail was launched through a 2014 Indiegogo campaign that raised more than US$550,000 within one month from more than 10,500 backers. The campaign's goal was $100,000.

Additional backers include Charles River Ventures and the Fondation Genevoise pour l'Innovation Technologique, a nonprofit foundation.

Users can upgrade to a paid account or donate money to help fund the company, which doesn't take ads.

"Since we do not violate user privacy to serve targeted advertisements, we cannot offer the service for free," Yen said. "[We charge for] more storage and advanced features, so that we can cover our operational expenses."

ProtonMail's encryption is fully compatible with PGO, "because PGP has withstood the test of time -- over 20 years now -- and is well trusted and vetted by the community," Yen said.

Other Secure Email Systems

Several other secure email systems are available.

For example, open source
Tutanota, which is based in Germany, offers a free option and a premium service for 12 euros yearly, and has mobile apps for iOS and Android. It encrypts all data on the user's device -- emails, contacts, subjects and attachments. It provides 1 GB of storage.

Kolabnow.com, like ProtonMail, is based in Switzerland. It's available for groups and hosting accounts, as well as individuals, and is priced from US$4.70 to $103 a month for hosting accounts with 10 users, payable in Swiss francs.

Gmail provides secure connections between a client and its servers, but data sent over the connection is plain text, noted Peter Eckersley, technology projects director at the Electronic Frontier Foundation.

"If Google receives an order from the FBI, they're going to have to disclose the text," he told TechNewsWorld.

Apple encrypts emails end to end, and it also encrypts messages sent through iMessage. However, iMessage backups go to Apple, which has access to the key, Eckersley said, "so if you backup to the iCloud, Apple can retrieve the data."

Encryption Is Here to Stay

The FBI has obtained a court order compelling Apple to assist it in accessing encrypted data, a move that has sparked strong emotions on both sides of the argument.

The release of yet another encrypted email system highlights one aspect of the debate. That is, even if the U.S. authorities should prevail in their case against Apple, there would still be many other encryption options that would not be subject to their investigations.

"We are supportive of Apple's efforts, but ultimately I don't think what happens in Switzerland will dramatically impact the outcome of that case," Yen remarked.

As far as encryption is concerned, the genie is already out of the bottle, Chen said, "and there's nothing to be gained by trying to legislate or control it. The sooner governments realize this, the sooner we can all work together to tackle the even more severe threats facing the Internet community today, such as the rise of cyberattacks and cyberterrorism. For that, encryption will be a hugely important defensive tool."

Richard Adhikari has written about high-tech for leading industry publications since the 1990s and wonders where it's all leading to. Will implanted RFID chips in humans be the Mark of the Beast? Will nanotech solve our coming food crisis? Does Sturgeon's Law still hold true? You can connect with Richard on
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